In a conventional process used in drilling, an open-faced drill bit is attached to a drill string, which is a series of connected drill rods and tools that are assembled section by section as the drill string moves deeper into a formation during a drilling operation. During drilling operations, the walls of the borehole sometimes become marred or deformed for a variety of reasons. For example, boreholes may develop doglegs, key seats, and ledges during normal drilling operations that tend to bind and damage drill strings and tools. For example, during drilling operations, the drill string sometimes deviates from directly vertical, making at slightly arced path through the formation being drilled. In such cases, withdrawing a drill string from the borehole can be problematic as the drill string can bind against the curved wall of the bore hole. In particular, the pipe connections of the drill string, being wider at the connections than the pipe lengths, tends to dig into the side wall of the borehole creating what is known as a keyseat.
Attempts to work the drill string loose can case the borehole to deform and even collapse, causing additional problems with the drilling. In extreme circumstances, portions of the drill string may be damaged or destroyed while being withdrawn from the borehole. Reamers and keyseat wipers have been used to maintain the condition of the sidewalls of boreholes and to stabilize the drill string in the borehole during drilling operations. Reamers generally use replaceable blocks and rollers in three or four locations around the reamer tool, as the blocks and rollers tend to become worn during drilling operations. Replacing blocks and rollers in reamer tools can be very difficult and time consuming as the blocks are generally pounded into place in slots in the tool and held from sliding by a bolt or pin. Additionally, traditional roller reamers include a shaft passing through the center of the reamer cutter around which the reamer cutter rotates. The creates the necessity of securing the shaft securely at both ends, necessitating the blocks that are pounded into place.